FIELD: polymers. SUBSTANCE: invention describes a composition for metathesis polymerization containing: a) one dicyclopentadiene or in mixture with complicated by cycloolefin and b) catalytical amount of cation-active ruthenium or osmium compound as a catalyst. Ruthenium or osmium compound corresponds to the compound of formulas: (VIII) (R26R27R28P)L1Me+2(Z1
1
)Z-
2
1, (VIIIa) (R26R27R28P)2L1Me+2(Z1
1
)Z-
2
1, (VIIIb) (R26R27R28P)L1L2Me+2(Z1
1
-)Z-
2
1, (VIIIc) (R26R27R28P)3L1Me+2(Z1
1
-)Z-
2
1 and (VIIId) (R26R27R28P)(L1)2Me+2(Z1
1
)Z-
2
1 where Me is Ru or Os; Z1 and Z2 mean independently each of other H-, cyclopentadienyl, Cl-,Br-,BF-
4
,PF-
6
,SbF-
6
,AsF-
6
,CF3SO-
3
,C6H5-SO-
3
, 4-methyl-C6H5-SO-
3
, 3,5-dimethyl-C6H5-SO-
3
, 2,4,6-trimethyl-C6H5-SO-
3
or 4-CF3-C6H5-SO-
3
; R26,R27 and R28 mean independently each of other hydrogen atom, unsubstituted C1-C6-alkyl or that is substituted with 1-3 C1-C4-alkyls, cyclopentyl or cyclohexyl, or cyclopentyloxyl, or cyclohexyloxyl or unsubstituted phenyl or benzyl or thats substituted with 1-3 C1-C4-alkyls or phenyloxyl or benzyloxyl; L1 means unsubstituted or substituted with 1-3 C1-C4-alkyls, C1-C4-alkoxyl, -OH, -F or Cl-C6-C16-arene or C5-C16-heteroarene or C1-C6-alkyl-CN, benzonitrile or benzylnitrile being L1 in the formula (VIIId) has different value if necessary; and L2 means H2O or C1-C6-alkanol. New composition is able to thermic polymerization (metathesis one) and useful for production of formed bodies and covers. EFFECT: improved properties of composition. 24 cl, 33 ex
